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請問如何利用ROWNUM安排坐位編坐?

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tabobomber
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註冊:2005-04-07

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#1 引用回覆 回覆 發表時間:2005-05-21 10:59:52 IP:203.55.xxx.xxx 未訂閱
謝謝各位。若現在有我十六個人的晚宴,一邊坐年長的,一邊坐年輕的,應怎樣用oracle寫出那個編排script來? 我現在寫了這麼多,但接著的實在不應如何是好。謝大家幫忙一下。 Alter Table member Add SeatNumber Number; Update member SET SeatNumber = ROWNUM; PROMPT========================================================; PROMPT YOUNGEST PLAYER IN THE CLUB PROMPT========================================================; Select Surname, GivenName, dateOfBirth, SeatNumber From (SELECT Surname, GivenName ,dateOfBirth, SeatNumber FROM member Order by dateOfBirth DESC) WHERE ROWNUM <=8; PROMPT========================================================; PROMPT OLDEST PLAYER IN THE CLUB PROMPT========================================================; Select Surname, GivenName, dateOfBirth, SeatNumber From (SELECT Surname, GivenName ,dateOfBirth, SeatNumber FROM member Order by dateOfBirth) WHERE ROWNUM <=8; 接著應如何用cursor or PL/SQL編排坐位? 是否應這樣?我實在攪不懂 DECLARE v_ SeatNumber member. SeatNumber %type; v_ dateOfBirth member. dateOfBirth %type; BEGIN IF v_ dateOfBirth > ?. THEN v_ SeatNumber : > 'Youngest'; ELSLF v_ dateOfBirth < ?. THEN v_ SeatNumber : > 'Oldest' ; END IF; DBMS_OUTPUT.PUT_LINE (??.) END; IDEA: / SELECT DECODE(ROWNUM-min_sno,0,a......,NULL) dept,DECODE(ROWNUM-min_sno,0,1,rownum 1-min_sno) sno,a......,surname FROM (SELECT * FROM member ORDER BY ....,.... ) a, ( SELECT dept,MIN(rownum) min_sno FROM ( SELECT * FROM member ORDER BY .....,surname ) GROUP BY ............. ) b WHERE a.........=b............ / 對不起大家。請問能否幫助一下?
Mickey
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#2 引用回覆 回覆 發表時間:2005-05-23 21:30:44 IP:218.32.xxx.xxx 未訂閱
說實在話, 希望別介意 Select Surname, GivenName, dateOfBirth, SeatNumber From (SELECT Surname, GivenName ,dateOfBirth, SeatNumber FROM member Order by dateOfBirth DESC) WHERE ROWNUM <=8; 與 SELECT Surname, GivenName ,dateOfBirth, SeatNumber FROM member WHERE ROWNUM <=8 Order by dateOfBirth DESC; 有何不同 ? 後續的 PL/SQL, 也是不太解耶.
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